HEBER CITY -- Classes are back in session after a carbon monoxide scare at Heber Valley Elementary School sent 17 students and a teacher to the hospital.
Hospital spokeswoman Amy Tuddenham says patients started arriving at Heber Valley Medical Center about 4:45 p.m. Tuesday, but all patients had been treated and released within two hours.
Fire officials say construction equipment being used to build additional classrooms set off the school's carbon monoxide detectors about 10:30 a.m. Tuesday.
The school was evacuated and a fire marshal tested for the toxic gas, which was detected only in one area.
But emergency crews responded again a few hours later when students started complaining of stomach aches and headaches.
Wasatch County Health Department spokesman Dallin Koecher tells the Salt Lake Tribune children were never in serious danger.